1. Field of the Invention
The present invention relates to lamp indicators for digital signal cross-connect (DSX) frames. More particularly, the present invention pertains to those DSX frames utilizing power amplifiers and flasher circuits connected to shelve lamp indicators or rack tamp indicators for indicating to the technician which shelf or rack to find the flashing tracer lamp indicator.
2. Description of the Prior Art
Presently tracer lamps, usually small LEDs, are utilized in communication offices to indicate the other end of a cross connected circuit (T-1 or DS3). Each tracer lamp is located on a particular shelf in a particular rack of a particular row. There are generally several rows in any communications office, each row having several racks of shelves. The tracer lamp indicators flash when first engaged by a monitor chord for approximately forty-five (45) seconds. This is to give the technician enough time to find the other end of the circuit. After the forty-five (45) has expired, the tracer lamp remains on constantly until the monitor chord is removed.
U.S. Pat. No. 4,670,626 issued Jun. 2, 1987 to Thomas M. Fisher discloses a cross-connect frame for digital signals having a shelf chassis in which a plurality of monitor jacks are connected in series with light emitting diodes (LEDs) along a tracer wire connection to indicate which line is being monitored.
U.S. Pat. No. 4,618,194 issued Oct. 21, 1986 to Jerald J. Kwilos discloses two timers activated upon the insertion of a monitor jack, the first causing the appropriate tracer lamp LED to flash at a predetermined rate and the second causing the tracer lamp LED to cease flashing and remain on constantly.
Monitoring the Performance of Digital Multiplex Circuits, an article written by Al Geigel, Bell Laboratories Record, Vol. 49, No. 7, in August of 1971, discloses the use of audible signals and visual signals on a monitor to indicate to maintenance personnel the existence of a fault in the multiplexer-demultiplexer frame of a digital signal cross-connect frame system, as well as the use of indicator lamps to indicate to the technician which multiplexer or demultiplexer was being monitored when the alarm occurred, which input or output was being monitored, and whether the alarm was due to bit errors or code violations.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.